Arc Machines M96, Руководство по эксплуатации

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Doc No. 740048 13
MODEL 96
TUBE TO TUBESHEET WELD HEAD
OPERATION MANUAL
6.0 ELECTRODE GEOMETRY AND INSTALLATION (Cont’d.)
6.8 Projected or recessed tubes.
If your tubes ends are projected above or recessed below the surface
of the tubesheet, they can still be welded, however since there are so
many possible combinations of materials, projection or recess
dimensions, tube sizes and wall thicknesses, consult the factory for
recommendations.
6.9 Electrode radial positioning.
The electrode must be positioned with respect to the tube O.D. Most
applications work best with the centerline of the electrode either in line
with the tube O.D., or slightly outside the tube O.D.
CAUTION
POSITIONING THE ELECTRODE TOO CLOSE TO THE TUBE I.D. CAN
CAUSE THE WELD PUDDLE TO “ROLL” INTO THE TUBE I.D.,
PREVENTING THE REMOVAL OF THE MANDREL.
BEFORE WELDING YOUR TUBESHEET, VARIFY THE WELD HEAD
SET UP AND WELD SCHEDLE ON A SACRIFICIAL TUBESHEET
MOCK UP.
6.10 With a mandrel installed (see 5.0 for mandrel installation) slide a
piece of tube (the same size as the tubes in the tubesheet) onto the
mandrel, far enough to reach within 3/8” (10mm) of the electrode
tip. Expand the mandrel by pressing the air valve down. Loosen the
pivot screw in the electrode holder, and position the electrode with
respect to the tube O.D., then tighten the pivot screw. See fig. 10.